1989 Mazda Truck Injectors are not getting a signal to inje

Tiny
RADSGUY
  • MEMBER
  • 1989 MAZDA TRUCK
  • 4 CYL
  • 4WD
  • MANUAL
  • 200,000 MILES
Highly maintained Mazda B2600i that has been running like new and passed smog with flying colors began to have difficulty starting afer sittng for 24 hrs.
The fuel pressure regulator was above spec and replaced. Fuel pressure is fine, pump is working. Spark is good. It appears that we are not getting a signal to the injectors to fire. We replaced the distributor and still have the same problem. What is the mechanism or suggestion as to how to get signal to the injectors.
Thank you so much if help can be provided. Fee will be paid for corrective feedback!
Bob
Ps. No engine light indicator on.
Monday, March 30th, 2009 AT 4:28 PM

6 Replies

Tiny
JAMES W.
  • MECHANIC
  • 2,395 POSTS
If you have spark, this means the timing input to the computer is good. Have you checked injector pulse with a "noid" or a test light? If yes, and you have no pulse, the signal to fire the injectors come directly from the ECM and I would say this part of the ECM has failed.
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Monday, March 30th, 2009 AT 10:15 PM
Tiny
RADSGUY
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Thank you for your reply. I need the diagram of the ECM connector indicating pin definitions. Are you able to provide for final testing? I am having a hard time finding another unit and quite surprised at the costs for those that say they have them.
Thanks!
Bob
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Tuesday, March 31st, 2009 AT 7:20 PM
Tiny
JAMES W.
  • MECHANIC
  • 2,395 POSTS
I can attach a diagram to this post for your ECM. The problem is, the diagrams are quite detailed and because of space limitations, they don't come through very well. If you give me your email address, I can send you a PDF which will be much clearer.
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Tuesday, March 31st, 2009 AT 8:58 PM
Tiny
RADSGUY
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Sure.
Silvab@radiological. Com
Thank you!
Bob
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Wednesday, April 1st, 2009 AT 11:30 AM
Tiny
RADSGUY
  • MEMBER
  • 4 POSTS
James-
The diagrams that you sent appear to be for a carburated engine. Odd that the diagram indicates 2600i. Am I incorrect? Is there also a diagram that shows the connector with pin labels?
Bob
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Wednesday, April 1st, 2009 AT 3:16 PM
Tiny
JAMES W.
  • MECHANIC
  • 2,395 POSTS
My listing showed several models for '89 B2600, but the injection diagrams will be the same for all models. If you still have a question, let me know, Jim.
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Wednesday, April 1st, 2009 AT 3:41 PM

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